Lock key



P. w. oLsoN Dec. 3, 1935.

LOCK KEY Filed Feb. 20. 1934 2 INVENTOR. Pkz'llzp 71/ 6% BY PatentedDec. 3, 1935 UNITED STATES PATENT OFFICE LOCK KEY Phillip W. Olson,Grand Rapids, Mich., assignor I Application February 20, 1934, SerialNo, 712,239

8Claims.

This invention relates to inventions for improvements in lock keys, moreespecially for use with a type of lock such as described in my copendingapplication, Serial Number 712,240 filed February 20, 1934.

In keys having deviating grooves in the sides hereof, the grooves havecustomarily been formed by making a single cut with an end milling tool.Accordingly, to make a key,'it was only necessary to locate theunlocking position of the tumbler lugs; then use an end cutter whichwould cut a groove slightly wider than the diameter of the lugs, forclearance; and mill a groove which would pass through the centers of thelugs.

Objects of this invention are to provide a key which is more difilcultto make or reproduce; to provide a key in which the significant tumblerlocating surfaces are extremely difficult to ascertain; and in which notonly the final position of the tumbler lug must be known, but also thedirection in which the tumbler must be moved.

Other objects is to provide a key for operat ing oppositely moveabletumblers which is adapted for being accurately guided longitudinally inthe keyway so that the tumblers will be correctly positioned when thekey is inserted at a predetermined depth.

Other objects and advantages will become apparent in the followingdescription, taken with reference to the accompanying drawing, in whichan illustrative embodiment of the invention is shown. 3

, Fig. l is a transverse section of a lock barrel having a cylindricaltumbler plug, for illustrating the use of a key of this invention.

Fig. 2 is an end view' of the plug with a key inserted, the key beingshown in cross section.

, Fig. 3 is a diagrammatic view showing the key being inserted in alock, the outline of the side elevation of the plug being shown inbroken lines, and the set of tumblers which are operated by the groovein one side of the key being shown in full lines in front of the key.

Fig. 4 is a diagrammatic view similar to Fig, 3, with the keyv fullyinserted to withdraw the tumblers completely into the plug. I

The lock, which is more fully shown and described in said application,comprises a cylindrical barrel 5 which is to be fixedly mounted in alock housing; and in the barrel is rotatably mounted a cylindricaltumbler plug 6, ,which may be connected to the lock bolt in anysuitable, well known manner. I

The cylinder has a longitudinal keyway 8 extending therethrough, and aplurality of transare flush with the surface of the plug when the (Cl.-9l

verse tumbler slots 9 arranged on either or both sides of the keyway. Inthe slots are slidably mounted tumblers comprising pairs of plates l0and II which have longitudinal apertures H in which a spring I 2 isplaced for pressing the plates 5 outwardly and projecting theirends intolooking grooves i3 which extend longitudinally in the walls of the boreIQ of the barrel.

Each plate is provided with a key engaging lug I5 which projects intothe keyway, and the outward movement of the plates is limited by shoul=ders l6, formed on the inner edges thereof, which contact with the topand bottom of the keyway. The length of the plates is such that theirends 15 plates are completely withdrawn into the plug in unlockingposition, and either end will project at the slightest movement from theunlocking position to engage in the grooves l3 and prevent rotation ofthe plug.

. A key I! is provided which has a rectangular section'blade l8 whichclosely guided in the keyway I, and the insertion of which is limited byshoulders l9, which contact with the face of the plug. In each faceofthe blade is provided 25 an irregular longitudinal groove 20 foroperating the adjacent row of tumblers; and the grooves open-into theangle of a V-shaped notch 2| provided in the end of the key, so that, ininserting the key, as shown in Fig. 3, the lugs are drawn 30 togetherand enter the grooves.

Since the tumbler plates are' spring pressed in opposite directions, thelugs will bear against the opposite sides of the groove, and significantsurfaces 22for determining the position of the up- 35 wardly pressedplates will be provided'in the upper side of the groove,;and thesurfaces 23, for positioning the downwardly pressed tumblers will 7occur in the lower side of the groove. Consequently there is no fixedrelation between the sides 40 of the groove, nor between either side andthe center line of the groove.

Accordingly, in making the key, it is necessary to locate surfacesinstead ofcenter lines. The surfaces in one side of the groove aredetermined, 45

V and a cut is milled to include these surfaces.

of the lugs in unlocking position. 5

Having thus described my invention, I claim: 1-. A key for a lock havingspring pressed tumblers, the key having a flat blade having a groove inone face thereoffor receiving cooperative portions of lock tumblers, theopposite sides of the same groove having predetermined unrelatedcontours for moving some of the tumblers at one side of the key up andothers at the same side of the key down into unlocking position.

2. A lock key having a flat blade for filling a key way, the bladehaving irregular grooves in the faces thereof and the sides of eachgroove having predetermined unrelated contours for en-- gaging withprojecting portions of oppositely spring pressed tumblers for moving thetumblers upwardly and downwardly for unlocking.

3. Alock key having a flat blade insertable in a keyway, the bladehaving deviating grooves in the faces thereof and the sides of eachgroove having predetermined unrelated contours for engagement with thetumblers of the lock.

4. A lock key having a blade adapted to fill and flt a keyway, the bladehaving deviating.

grooves in the faces thereof, the sides of each groove having unrelatedcontours for positioning transversely movable tumblers in oppositedirections.

5. A key for a lock having transversely mov-' able tumblers springpressed in opposite directions, the key having a blade which islongitudinally insertable in the lock and has deviating grooves in thefaces thereof, the sidesof each groove having predetermined unrelatedcontours for cooperating with the tumblers and positioning the same forunlocking.

6. A key'for a lock having a row of tumblers having projecting lugs andlaterally movablein oppositedirections for unlocking, the key beinginsertable in the lock to a predetermined'depth and having alongitudinal irregular groove for receiving the lugs of the tumblers,the surfaces I for positioning the tumblers which are movable in onedirection being provided in one of the sides of the groove, andindependently contoured surfaces for positioning the oppositely movabletumblers being provided in the opposite side of the same groove. v 7. Akey for a lock having pairs of adjacent transversely movable tumblersspring-pressed in opposite directions, the key having a bladelongitudinally insertable in the lock with grooves in the faces thereof,the sides of each groove having independent contours for positioning theadja:ent movable tumblers in opposite directions.

8. A key for a lock having transverse slots and a pair of transverselymovable spring-pressed tumblers in each slot, the key having, a bladeinsertable in the lock with grooves in the faces thereof for receivingthe lugs of the tumblers, and the sides of each groove havingindependent contours for positioning the transversely movable tumblersof each pair in opposite directions.

PHILLIP w. oisoN.

